When to Plant Hostas in Wyoming
The king of shade gardens. Hostas come in hundreds of varieties and get more beautiful with each passing year.
The Short Answer
Wyoming Frost Dates
Your planting dates depend on which part of Wyoming you're in. Here are the frost date ranges by region:
| Region | Zones | Last Frost (Spring) | First Frost (Fall) |
|---|---|---|---|
| Eastern Wyoming | 4a, 4b, 5a | May 10 - May 30 | Sep 10 - Sep 25 |
| Western Wyoming | 3a, 3b, 4a | May 25 - Jun 15 | Aug 25 - Sep 15 |
| Southern Wyoming | 4b, 5a, 5b | May 15 - Jun 1 | Sep 5 - Sep 20 |
Hostas Planting Schedule for Wyoming
Eastern Wyoming (Zones 4a, 4b, 5a)
Average last frost: May 10 - May 30 · Average first frost: Sep 10 - Sep 25
Western Wyoming (Zones 3a, 3b, 4a)
Average last frost: May 25 - Jun 15 · Average first frost: Aug 25 - Sep 15
Southern Wyoming (Zones 4b, 5a, 5b)
Average last frost: May 15 - Jun 1 · Average first frost: Sep 5 - Sep 20
Growing Hostas in Wyoming
Hostas in Wyoming's Climate
Your climate is hosta heaven. Cold winters provide necessary dormancy, moderate summers prevent heat scorch, and abundant shade from deciduous forests creates ideal growing conditions. Michigan, Minnesota, and Wisconsin grow some of the finest hostas in the country. The only pest concern is slugs — iron phosphate bait handles them.
Soil Considerations for Wyoming
Alkaline, thin soils. Dry climate means little organic matter naturally. Wind erosion a significant challenge. Heavy amendment needed.
Wyoming Climate & Growing Season
Short growing season. Very windy — wind protection essential for gardens. Low humidity. Cool nights even in summer at elevation. Hostas can handle frost well, which is an advantage in Wyoming's climate. You can push planting dates earlier in spring and extend into fall.
Growing season length varies across Wyoming: Eastern Wyoming (4a, 4b, 5a) has a last frost around May 10 - May 30, while Southern Wyoming (4b, 5a, 5b) sees frost end around May 15 - Jun 1. This difference matters for hostas — adjust your planting dates to match your specific region.
Growing Tips
Plant divisions or nursery plants in spring or fall. Slugs are the main enemy — use iron phosphate bait. Mulch to retain moisture.
Companion Planting
Plant hostas alongside these companions for better growth:
The Bottom Line
Last reviewed: March 29, 2026